Study finds half of Canada's vertebrate wildlife species are in decline

Habitat loss, pollution, climate change have all contributed to steep declines of some species since 1970

A study by WWF-Canada finds that habitat loss, pollution and climate change have all contributed to the precipitous decline of some Canadian species, such as the barren-ground caribou. (Photo: Elaine Kennedy/Can Geo Photo Club)

Half of Canada's vertebrate wildlife species have experienced population declines in the past 40 years, according to an alarming new report from WWF-Canada.

The Living Planet Report Canada, a national look at species loss published Thursday, highlights population trends for just over 900 vertebrate species, including 106 species of mammals, 386 bird species, 365 fish species and 46 reptiles and amphibians. Of the monitored species, 50 per cent were found to have declined between 1970 and 2014 — and for most, the decline was steep.

"The results of our study indicate that wildlife loss is a Canadian problem and that collectively we need to do more to prevent the loss of wildlife in Canada," says James Snider, Vice-President of Science, Research and Innovation for WWF-Canada.

Habitat fragmentation, pollution, climate change impacts and invasive species were common factors driving the decline of species across regions and ecosystems. The problem, Snider notes, is that these stressors rarely occur in isolation; for example, climate change can accelerate the spread of invasive species by creating favourable living conditions in areas that were once inhospitable.

"There are usually two or more stressors for any given at-risk species, which means our job for recovery and conservation of species in Canada is even more challenging."

The study zeroed in on 64 species that have been protected under the federal Species At Risk Act (SARA) since it was enacted in 2002 and found their numbers actually continued to decline, calling into question the effectiveness of the legislation. Currently, species are assessed by an independent advisory board known as the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), but receive no formal protection under the Species at Risk Act (SARA) until the federal cabinet acts on COSEWIC's advice. And even once a species is listed, a recovery plan is rarely developed in the timeframe specified in the act. The St. Lawrence beluga whale population was SARA-listed as Threatened in 2005, but it took more than a decade for the whales' summer breeding grounds to receive full legal protection.

Snider says that while efforts should be made to speed up the process of implementing SARA protections, more should be done to prevent species from becoming imperilled in the first place. That will require ongoing research to understand how species are responding to threats like climate change, particularly in underreported areas such as the Arctic.

"We need to build a nationwide monitoring program to really, truly understand these patterns of wildlife change," Snider says. "That extends beyond government — there are roles individuals and industry can play in preventing species from becoming at-risk."

Species spotlight

Some of the species that have experienced the steepest declines since 1970

Barren-ground caribouLatest COSEWIC assessment: Threatened

Barren-ground caribou once numbered in the millions across the Canadian Arctic but now have an estimated total population of 800,000. While that might not sound like a crisis, some herds are estimated to have declined by 90 per cent or more from peak numbers. As the Arctic warms, the region is increasingly opening up to resource development and tourism that could fragment the caribou's habitat. In 2016, COSEWIC warned that if action is not taken now to protect calving grounds, the species could soon become endangered.

Little brown batLatest COSEWIC assessment: Endangered

In spite of their spooky reputation, little brown bats play an important role in balancing ecosystems thanks to their voracious consumption of insects such as mosquitos and flies. Their numbers are dropping due to a fungal disease called white-nose syndrome that disrupts their hibernation and causes them to use up their stored energy reserves too quickly. Within three years of its discovery in eastern Canada, white-nose syndrome had wiped out 94 per cent of hibernating little brown bats in New Brunswick, Nova Scotia, Quebec and Ontario, and could infect the bat's entire Canadian range by 2028.

Chinook salmon Latest COSEWIC assessment: Threatened

Chinook salmon, the largest of the Pacific salmon species, are an example of how the decline of one species can have a ripple effect throughout an entire ecosystem. As annual chinook returns have plummeted, researchers have noted a corresponding decline in the population of southern resident killer whales, which feed almost exclusively on the salmon. And, as this grizzly bear researcher points out, the vanishing salmon put land-based species at risk as well: